共查询到20条相似文献,搜索用时 62 毫秒
1.
《环境与可持续发展》2015,(6)
本文通过对麻阳县生态环境特征的分析,并依据生态保护红线的划定目标,从重要生态功能区、禁止开发区和生物多样性保护区等方面建立了麻阳县生态保护红线划定指标体系,并确定其技术方法。运用空间统计分析、GIS叠加分析等技术,划定麻阳县I类和II类生态保护红线,从而确定了区域内生态保护的重点与方向,对麻阳县开展生态环境保护管理工作具有重大意义,也为其它县、市划定生态保护红线提供参考。 相似文献
2.
3.
《环境保护》2017,(23)
划定生态保护红线是加大生态保护力度的重要抓手之一,建立完善的生态补偿机制是推动生态保护红线政策落实的重要保障。近年来,我国生态补偿制度框架日渐清晰和明确,但由于涉及生态保护红线的区域范围广、面积大,目前对这些区域的生态补偿与生态保护的要求还有一定的差距。因此,本文深入研究了在重点生态功能区转移支付基础上拓展生态保护红线生态补偿的基础和条件,认为生态保护红线生态补偿制度可依托重点生态功能区转移支付"借梯上楼",不断优化转移支付系数,扩大对生态保护红线涉及县域的补偿,同时还提出了生态保护红线区域之间横向财政转移支付,以及园区合作式补偿、社会保障式补偿、市场补偿等非资金形式的横向生态补偿的思路建议。 相似文献
4.
《能源环境保护》2017,(4)
以秦岭北麓(西安段)为研究对象,在研究分析秦岭地区生态环境现状特征的基础上,利用ArcGIS软件,重要生态功能区评价指标选取生物多样性保护、水源涵养2项评价因素开展生态系统服务功能重要性评价,划定重要生态功能区红线;根据地方相关法规和规划,划定禁止开发区红线。将重要生态功能服务区红线与禁止开发区红线叠加,最终划定秦岭北麓(西安段)生态功能红线。其中,重要生态功能区水源涵养保护红线区面积达2 157 km~2,占全区总面积41.5%;禁止开发区范围面积约2 076 km~2,占全区总面积39.9%。叠加构成秦岭北麓(西安段)的生态红线区总面积3 157 km~2,占区域总面积的60.7%。秦岭生态红线范围的划定为秦岭生态环境保护提供理论基础。 相似文献
5.
《环境与可持续发展》2017,(1)
生态保护红线的划定是山东省推进生态文明建设的重要举措。文中介绍了山东省生态保护红线划定的背景、组织形式、划定原则、划定范围和方法以及划定结果,分析了生态保护红线划定之后的管理策略,总结了生态保护红线划定经验,提出了生态保护红线制度体系构建建议,为其他省市生态保护红线划定提供参考和借鉴。 相似文献
6.
7.
8.
10.
加快“三个落实” 建立生态保护红线制度 总被引:4,自引:0,他引:4
划定并严守生态保护红线是保障国家和区域生态安全的客观需求,是贯彻落实新时期中共中央强化生态环境保护的更高要求,是全面深化改革、促进生态文明制度建设的重要举措。自2011年国务院提出划定生态保护红线任务以来,经过多年努力探索,政府和学界在生态保护红线划定与管理方面开展了很多有益实践,但仍存在思路不统一、部分地区进展缓慢、配套政策不明确等问题。当前,划定生态保护红线已明确列入"十三五"生态文明建设重点任务,针对生态保护红线制度落地关键问题,从边界范围、配套政策及管控体系三个方面,提出了加快"三个落实"的对策措施,为实现严守生态保护红线提供科学依据。 相似文献
11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera. 相似文献
12.
Arsenic uptake by arbuscular mycorrhizal maize (Zea mays L.) grown in an arsenic-contaminated soil with added phosphorus 总被引:1,自引:0,他引:1
XIA Yun-sheng CHEN Bao-dong CHRISTIE Peter SMITH F Andrew WANG You-shan LI Xiao-lin 《环境科学学报(英文版)》2007,19(10):1245-1251
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility. 相似文献
13.
Several main metabolites of benzo[a]pyrene (BaP) formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone (BP 1,6- quinone), trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP 7,8-diol), 3-hydroxybenzo[a]pyrene (3-OHBP), were identified by high-performance liquid chromatography (HPLC). The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that (1) the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; (2) the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; (3) the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% (w/v), concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites. 相似文献
14.
Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter. 相似文献
15.
DING Zhen-hu TANG Qing-he LIU Cai-e WANG Wen-hu ZHUANG Min LIN Yi-ming 《环境科学学报(英文版)》2007,19(2):200-204
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants. 相似文献
16.
Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA. 相似文献
17.
Decomposition of alachlor by ozonation and its mechanism 总被引:1,自引:0,他引:1
Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor. 相似文献
18.
The influence of the nonionic surfactant Tween 80 on pentachlorophenol (PCP) oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration (CMC). Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme. 相似文献
19.
Potential of plant polyphenol oxidases in the decolorization and removal of textile and non-textile dyes 总被引:2,自引:0,他引:2
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation. 相似文献
20.
Removal of heavy metals from sewage sludge by low costing chemical method and recycling in agriculture 总被引:7,自引:0,他引:7
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF... 相似文献